Removal of special characters from csv file

Currently, the Jupyter file - [Section_extraction](https://github.com/prateekguptaiiitk/Resume_Classifier/blob/development/Section_Extraction.ipynb) creates a [CSV file](https://github.com/prateekguptaiiitk/Resume_Classifier/blob/development/prc_data.csv) which includes special characters in its sections. Removal of them is an important task.